approve vs transfer
These two words describe very different actions, and confusing them is how people get drained.
transfer
A transfer actually moves tokens from one address to another. When you send tokens, or a contract moves them on your behalf, value changes hands immediately.
approve
An approve moves nothing. It records a permission: “this spender may move up to this amount of my token.” The tokens stay in your wallet. The danger is that the permission can be used later, by the spender, without asking you again.
Why it matters
- A site that only needs to move a fixed amount should ask for that amount, not an unlimited approval.
- An approval is only as safe as the contract holding it. If that contract is exploited, your allowance can be used against you.
- Old approvals accumulate. Each one is a standing permission you may have forgotten.
What to do
Read what you are signing. Prefer specific amounts. Revoke what you no longer need. And watch for new approvals — Shingan alerts you when one appears on your wallets.